Garfield County

Garfield County is a county located in the U.S. state of Washington. As of the 2010 census, the population was 2,266, making it the least populous county in Washington; with about 3.2 inhabitants per square mile , it is also the least densely populated county in Washington. The county seat and only city is Pomeroy.
The area delineated by the future Washington state boundary began to be colonized at the start of the nineteenth century, both by Americans and British. However, the majority of British exploration and interest in the land was due to the fur trade, whereas American settlers were principally seeking land for agriculture and cattle raising. The Treaty of 1818 provided for the creation of a British and American condominium over the region. During this period, the future Washington Territory was divided into two administrative zones: Clark County and Lewis County . However, the condominium arrangement was unwieldy, leading to continuous disputes and occasional conflict; it was abolished by an 1846 treaty that established a boundary between British and American possessions that survives as today's Canada–United States border.

Wikipedia